652 FXUS63 KFSD 290006 AFDFSD AREA FORECAST DISCUSSION National Weather Service Sioux Falls SD 706 PM CDT Fri Jun 28 2019 .SHORT TERM...(This Evening through Saturday) Issued at 308 PM CDT Fri Jun 28 2019 Moisture and associated cloud cover trapped below the inversion has been tough to shake so far today with a few pockets of better sunshine across the region. This has kept temperatures a couple degrees cooler than their potential thus far but with dewpoint values in the 70s, heat indices remain quite uncomfortable. Will let going Heat Advisory continue as scheduled. Temperatures tonight remain mild, generally only falling into the lower 70s. This will set the stage for another very warm day Saturday. While we may battle some initial cloud cover again tomorrow morning, with 850 mb temperatures in the upper couple percentiles of climatology and 925 mb temps in the mid to upper 20s C, expect widespread 90s across the region by afternoon. With the continued muggy dewpoints, heat indices should run near or above 100 for most areas and thus issued another Heat Advisory for Saturday afternoon and early evening. .LONG TERM...(Saturday Night through Friday) Issued at 308 PM CDT Fri Jun 28 2019 By Saturday evening, a weak impulse running over the surface boundary to our north should be enough to spark shower and thunderstorm development. Consensus from the large scale deterministic models and most CAMs is to keep any of this activity void of our forecast area but the nested NAM and to a lesser extent NMM WRF sneak some of this activity into areas north of I-90 Saturday night. Have introduced some slight chance POPs for this potential but confidence is quite low in these solutions. This previously mentioned thunderstorm activity, along with the surface boundary location, will be critical to Sunday's forecast. Areas south of the boundary and void of any convective contamination will see another very warm day Sunday. In fact, may even see dewpoint pool some along and just south of the boundary. Will likely need another Heat Advisory for at least portions of the area but given uncertainties with the factors mentioned above, will defer this decision to future shifts. This boundary will also serve as the focal point for additional thunderstorm development late Sunday and Sunday night. Again, areas north of I-90 currently appear to have the better chance of seeing this activity with enough instability present to keep a few strong to severe storms in the question and thus a Marginal risk from SPC. The much discussed surface boundary continues its meander its way around the area into early next week with continued chances of showers and thunderstorms. Tough to say much about the details at this point but plan on occasional precipitation chances. Temperatures will also retreat back into the 80s but will ultimately depend on boundary locations and convective contamination. && .AVIATION...(For the 00Z TAFS through 00Z Saturday evening) Issued at 651 PM CDT Fri Jun 28 2019 Mainly VFR conditions expected. Models suggest a potential for patchy fog or lower stratus developing under an inversion late tonight into Saturday morning. Confidence is fairly low at this point, so will have to monitor. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...Heat Advisory until 8 PM CDT this evening for SDZ050-052-053- 057>071. Heat Advisory from 1 PM to 9 PM CDT Saturday for SDZ038>040-050- 052>071. MN...Heat Advisory from 1 PM to 9 PM CDT Saturday for MNZ071-072-080- 081-089-090-097-098. IA...Heat Advisory until 8 PM CDT this evening for IAZ012-020-031. Heat Advisory from 1 PM to 9 PM CDT Saturday for IAZ001>003- 012>014-020>022-031-032. NE...Heat Advisory until 8 PM CDT this evening for NEZ013-014. Heat Advisory from 1 PM to 9 PM CDT Saturday for NEZ013-014. && $$ SHORT TERM...Kalin LONG TERM...Kalin AVIATION...